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Archiving 1.44mb Floppy

I recently came across a very early shareware release of Doom and I wanted to back it up, but it appears the disk is deteriorating and I'm having some issues. I have Imagedisk installed on my tweener and I was trying to use that but I can't seem to get the formatting right and it doesn't want to copy weak bits. I do have an Option Board in my 5160 but I was hoping not to have to put it apart and put in a 1.44mb drive just to image this disk (has a 360k and 720k currently). What settings should I be using and is there a way to copy across weak bits with imagedisk to try and save the software?

Uh, DOOM isn't copy protected. There are not "weak bits" as used in copy protection, you just have a damaged disk.

Also, DOOM shareware versions should already be archived out there. Is there something specifically of interest about the version on this disk?

You can tell ImageDisk to keep bad sectors, but that only works if the floppy disk controller can find the sector header, otherwise you get a missing sector.

But lets back up for a moment. Before putting a non-well stored floppy disk in a drive, one should first inspect the surface of the disk to look for debris, residue, and existing damage. Did you do that?

If there is visible debris or dirt on the disk, a q-tip and a bit of water should be able to remove it. That may still help even after you have already run it through a drive. (Don't use alcohol if it is shedding)

If it is shedding oxide, it may be too late now that you have run it through a drive.

Now, as for recovering bits, technically a deluxe option board/transcopy board records everything at the flux level, but the tools for working with the TC file format are few and limited. (The only one I know of are the tools included with the PCE emulator, and I think that only works with low density images, not high density or Apple GCR). If you really wanted to recover bits, I'd recommend a Kryoflux. There are multiple tools you can use to "decode" a sector image, and some can have better results than others. You can also (with the PCE tools) decode to a text file, that lets you manually reconstruct sector headers and data. If you manged to read the sector CRC, you can use pattern matching to recreate the contents.

although, since this is not a copy protected disk, that would be an overkill.

Another thing to try, is just trying the disk in different floppy drives. There are dozens of tiny factors that can differ between drives and can affect the readability of a specific disk.

Also, instead of ImageDisk, you might try trixer's disk2img. Instead of slowly reanalyzing, re-seeking, and retrying, it re-reads every time the sector passes over the head. Very handy if the data is there, but reading is hampered by nearby scratches or shedding. Fiddling with the drive head while reading will create immediately visible results using this program. http://www.oldskool.org/pc/disk2img

does the disk label report what version it is? If you can find that info, we can look it up to see if it has already been archived. Chances are quite good there is a copy available already out there. Even the Press Beta and Alpha releases of DOOM have been preserved.

Central Point PC Tools Deluxe has a "Revitalise a disk(ette)" facility that does a pretty good job reading (with error correction off) multiple times, comparing the sector copies and re-writing multiple times to "recover" iffy sectors.